The present invention relates in general to setup jigs and tooling for wood-working routers and router bits. The present invention may also find applicability in gauge designs for setting the depth or positioning of various cutting tools. More specifically, the present invention relates to a setup jig for a router bit in order to set the desired router bit depth (i.e., height adjustment) for a selected style of cutting profile in the workpiece based upon the style of router bit selected.
In terms of the prior art, the most common apparata and method for making router bit height adjustments is to select and then use a wooden block that has been machined with the selected bit profile or style, set at a predetermined or standard height which would determine its relative position in the workpiece. The desired block is selected and positioned on the router base plate and the router bit is loosened within the chuck or collet so that it can be extended. The router bit is moved axially into or out of the opening in the router base plate until the cutting or machining contours of the router bit match the machined form (profile) of the wooden block. In order to provide a variety of options for various wood-working projects, a plurality of blocks are required. Each block provides a single style of router shape, cut, or profile and a single depth or height for the corresponding cut. Most prior art products offer a limited number of cutting depth variations for a particular style or shape, if any. However, if a wood-worker wanted design and depth variations, such as having eight different router bit shapes or styles with two cutting depth choices each, a total of sixteen individual blocks would be required. As one alternative to this, the wood-worker could use a set of eight blocks for the eight different router bit shapes or styles and then use some type of spacer or shim stock beneath the individual block in order to vary the positioning of that profile between the outer planar surfaces of the selected workpiece.
In view of the number of different blocks and pieces and considering how difficult it might be to use spacers or shims to accurately vary the position of the profile within the workpiece, it would be an improvement to what presently exists if multiple router bit shapes or styles (profiles) could be integrated into one setup jig. Another improvement opportunity would be the ability to vary the height adjustment of the profile so as to provide a wider range in terms of acceptable workpiece thicknesses from some minimum thickness to maximum thickness compatible with the selected router bit profile. Within this minimum to maximum range, it would be an improvement to be able to incrementally select the desired height in an easily adjustable, accurate, and reliable manner.
The present invention is directed to overcoming the problems, disadvantages, and drawbacks of the prior art gauge blocks by integrating multiple router bit profiles into a single setup jig that also enables incremental height adjustments between minimum and maximum values. These incremental height adjustments allow the selected router bit profile to be located at different places within the thickness of the selected workpiece, depending on the particular project. All of this, as provided by the present invention, is created in a user-friendly, low-cost device that is precise and reliable.